However, two state offices in a building on Main Street and Third Street will remain sealed until test results show a suspect envelope was not contaminated with the bacterium, said Bob King, spokesman for the governor.

"We're taking every precaution," said King, who expected lab results on the envelope by Tuesday.

The state workers were tested for anthrax exposure after an employee who works at a structure known as the Community Building opened a letter on Friday and saw a puff of powder. The employees alerted authorities, who evacuated and sealed two rooms in the building, which houses some offices of the state Department of Education and Early Development.

The envelope contained a check from an Alaska school district and had no visible signs of powder inside, but the state ran the nasal tests as a precaution, King said.

"I think it confirms what our expectations were and hopefully it will be a relief to the individuals involved and their families as well as their co-workers and others," King said. "But I'd like to stress the proper procedures to take were followed in this case."

The envelope was mailed to the state by the Copper River School District, which partially funds its hot lunch program through the state Department of Education and routinely sends checks to the Juneau office, said superintendent Tom Rother.

Rother offered a possible explanation for the powder puff, saying a district employee might have inadvertently dropped coffee creamer into the envelope.

"The mailroom is by the cafeteria," Rother said. "Somebody could have been taking the letter to the mailroom and grabbed a cup of coffee while they were doing it and got some creamer on it."

Rother said the Juneau workers did the right thing by immediately alerting authorities.

"I don't look at it as people overreacting. I look at it as people being cautious," he said.

The Juneau workers tested for anthrax exposure include two employees who work in the office where the letter was opened, a supervisor, a mail room clerk plus two other employees who walked into the office. Their names were not released.

The state also is following up on other reports of suspicious mail, said King, the governor's spokesperson. In two incidents, the National Guard in Kodiak and a post office at an Anchorage airport received large envelopes postmarked Saudi Arabia. The envelopes contained only religious tracts with no visible powder, but the state tested them for anthrax as a precaution, King said. The Kodiak test came back negative on Monday and the state is awaiting results on the other, he said.

The state today sent a memo to employees advising them how to handle suspicious letters or packages. The memo refers to an advisory by the FBI, which recommends against bumping, shaking, opening or smelling suspicious parcels.

The FBI, which investigated the Juneau case, also advises people to be on alert for certain signs, including misspelled words, excessive postage, no return address and postmarks from foreign countries.

Meanwhile, authorities in Anchorage and Sterling are investigating what appear to be anthrax hoaxes.

In Anchorage, police and firefighters responded Sunday afternoon to a call from workers at the Puffin Inn in the city's Spenard section.

Police said an employee at the inn found a pile of powder on the doormat with a note that said "anthrax." Police said they are investigating but added the incident appears to be a prank.

Police spokesman Ron McGee said his department responded to a number of calls over the weekend that ended up being anthrax hoaxes or false alarms. He said the calls waste time and resources but added that each report is taken seriously.

In Sterling on the Kenai Peninsula, authorities closed the Post Office for about three hours Saturday after a postal worker found a white substance in a mail bag, Alaska State Troopers said. The unknown substance, which looked like ground-up chalk, was seized.

Kathy Dye can be reached at kdye@juneauempire.com. The Associated Press contributed to this report.